Few issues are more emotional, and therefore vulnerable to bad analysis, than urban crime risk. Solid research indicates that more compact and mixed development tends to increase neighborhood security. Jane Jacobs was right!

An ambitious idea is gaining traction in Seattle, following in the footsteps of the city's waterfront remake. With the Lid I-5 campaign in the lead, advocates are exploring what it would take to fully lid I-5. "During construction in the early to mid 1960s," Knute Berger writes, "it had destroyed some 6,000 homes, slashed through the International District as it cut a concrete canyon through the heart of the city."

But times have changed. Recently, "a city grant has helped come up with concepts for how the new 'land' of a lid — a concrete cover to I-5 strong enough to hold buildings, parks, roads and people — could be used."

I-5 is already partially lidded in several places, like Freeway Park and the Washington State Convention Center. "As part of the package to expand the Washington State Convention Center, $1.5 million has been allocated to the city for an upcoming study of the feasibility of lidding which will be undertaken in 2019."

The project is bound to be expensive, complex, and will likely take many years to complete. But given downtown land prices, Berger writes, much of the cost "could well pencil out." In the meantime, the idea has sparked lively discussion about what might be done with all that new land, and a more cohesive downtown.

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